Realism and the wavefunction

Realism-the idea that the concepts in physical theories refer to 'things' existing in the real world-is introduced as a tool to analyse the status of the wavefunction. Although the physical entities are recognized by the existence of invariant quantities, examples from classical and quantum physics suggest that not all the theoretical terms refer to the entities: some terms refer to properties of the entities, and some terms have only an epistemic function. In particular, it is argued that the wavefunction may be written in terms of classical nonreferring and epistemic terms. The implications for realist interpretations of quantum mechanics and on the teaching of quantum physics are examined.